Rolling-mill for rolling out hollow blocks.



A. PASSL.

ROLLING MILL FOB. ROLLING OUT HOLLOW BLOUKSL APPLICATION FILED APR. 10,1000.

2 SHEETS-SHEET 1.

Patented 1 11.4, 1911. v

4 A. PASSL. VBOLLING MILL FOR BOLLINGOUT nomzow BLOCKS.

APPLIOATION FILED APR. 10, 190B.

Patented Apr. 4,-1911.

z sums-sum 2.

ql xtorsrassr', orw'nsma;

Fnssn, engineer,

the following rollers arranged transverselyv behind each other androtating at increasing speeds,

v wherein the core-bar in the first method is moved forward by. thefastest rotating pair ,of rollers provided with grooves forming av roundass, and in the second method is 3 'moved orward by the slowest pair ofrollers likewise provided withround grooves; The first metodnecessitates'a very long coref bar as the speed of the core-barand-work is equal.- In the second method the arrange 'ment of. the roundgrooved rollersat the efi'ecton uniform rolling and'even makes itentrance to the rolling mill'oflers a great disadvantage which greatlydiminishes the other advantages. Interruptions in the flow of the metalfrom one grooved roller to the other are caused by the core-bar movingforward-too slowly,"'this having an adverse uite. impossible; Thesedrawbacks assert t emselves more particularly when. soft metal is beingrolled. It is therefore desirable'that the core-bar should advance morerapidly than the groove of the first pair of rs and that e grooves in,said rollers should be of oval shape in order to be able to stretchmore readily. The advantage of a short. core-bar should however beretained in order that the rolled pipe is always longer than thecore-bar'during the rolling. T In order to attain these advantages, apair of rollers which are driven at a given speed are each provided wltha semi-circular groove whereby a trueround pass is formed between them.'The rollers on each side of these intermediate rollers are providedwith semi-oval grooves" wherebyan oval pass is formed between eizch pairof rollers. The

rollers which are the speed of the receiving rollers, or the rollers infront of theintermediate rollers being less than, the'speed of theintermediate rollers, while that of the delivering'rollers or. therollers inthe rear of the intermediate rollers is greater-.- The groovesin the sucrovided with the semioval grooves, are, rlven at variablespeeds,

flon o! Letters Patent. 5 a imation illeclApril 10, 1908. 'Serial No.426,846.,

aonnrnmmnron nonnnm our HOLLOW nnocxs.

' Patented Apr. 4, 1911.

cessive pairs of rollers on each side of the intermediate pair ofrollers are increased as to their greatest diameter, whereby each.successive pair of rollers, will resent a smaller surface which willcome in contact with the material being worked. The proportionatebroadening of the oval pass rollers, should, as far as possible,counteract the drawing or retardingact-ion of the corebar and thereb)prevent tearing or shortening of the work from one grooved roller to theother.-

In the accompanying drawings, Figure 1 is a top plan view of myinvention, Fig. 2 is 4 a side elevation of t-he'same, Fig. 3-is a bottomplan view; Fig. 4 is a detail side eleva tion of one pair of the rollershaving an oval passtherebetween, Fig. 5 is a detail side elevation ofthe intermediate pair of rollers, having'a true round pass therebetween,Fig. 6 is a detail sectional view'of the series of pairs of rollers witha section of the metal tubing to be rolled and the core bar or'mandrelin applied position, and Fi 7 illustrates the successive actions of thedi ferent pairs of rollers on the metal tubing.

In Figs. 1, 2, 3, 4 and 5, the ap roximate application of such arolling-mil is repre-.

- sented. In Fig. 1-. it can be seen, that all the rollers receive anincreased speed of rotation by the cogs a, b, c, d, e. f, g, as theyhave a decreasing diameter beginning from a.

These cog-wheels are fixed up in the co wheel standards 1' andare-connected wit the rollers e by coupling and alsoby thebevel-wheel's'lm n. The rollers, o enga e mutually by means of thecog-wheels i and a in order to receive 'the right direction of rotation.The pair of rollers 0 on which the passes are introduced, are marked .byl.- The arrangement of the horizontal rollers is es, pecially to be seenin Fig. 4, the arrangement of the vertical rollers being shown in Fig.5. Fig. 3 shows the horizontal rollers in section} Fig. 6 represents theschematic arrangement of thepairs of rollers, the material W in theaction of being rolled is shown in section, the said material W, as wellas the mandrel Q, moves forward in the direction of arrows.

In Fi 0 having oval forms. These oval passes press the material to berolled only on a 7, the corresponding passes are" shown, t e same, withthe exception of pass small part ofthe surface, of the mandrel, whilethe round pass encireles the mandrel closely on all sides. By thiscloseencircling on all sides, the mandrel Q is held so firmly that it canmove forward only at the speed.

of this round pass. This speed is always [greater-than that-of thepreceding first pair of rolls, and less than'that of the following last'pair of rolls and is the best taken from the middle pair of. rolls. Theintermediate pair of rollers, as has been stated heretofore, areprovided with semi-circular grooves, wlnch form a true round passbetween the said rollers. Therollel's' on each side of the intermediaterollers are provided with semi-oval grooves, whereby oval passes areformed .between each. of these pairs of rollers. vThe grooves in thesuccessive rollers eon each side of the intermediate-pair ofrollers'are' increased as to their greatest diameter. Thus,the pass ofthe first rollers and'the pass of the last rollers are the most oval,the same being able to exercise the least effect on the speed of themandrel, so that uous mill from an apertured blank over a mandrelcapable of movement inv the direction'of rolling as the same progresses,whlch consists in subjecting the blank when assembled on the mandrel toa rolling action in vsaid null, and lncreaslng the contaetlng area ofthe successive passes from the pair of rolls atthe entering end ofthemill, to the central pair of rolls and then decreasing the contactingarea of the successive passes to- Ward the final pair of rolls, wherebythe speed of the mandrel is. controlled by the speed of the center setof rolls.

'ALOY S 'FASSL;

. In presence of-- CARL STUPP, LOUIS Vannonn.

